1. Field of the Invention
The present invention relates to an electricity acquiring plug used in vehicle, more particularly to an electricity acquiring plug used in vehicle having auto fastening and rapid releasing functions.
2. Description of Related Art
A plug for lighting cigarette is often provided at a front panel of a vehicle, the round plug is a plug with 12V or 24V DC power. A conventional means is that a cigarette lighter is inserted in the cigarette-lighting plug; because said means involves a process of converting electrical energy into thermal energy so a high resistance value is generated, a fuse is often installed for providing a power breaking off function caused by over heating.
As for various portable electronic products have been developed, e.g. portable computers, mobile phones, personal digital assistant (PDA) and global positioning system (GPS), the cigarette-lighting plug (hereinafter referred as electricity acquiring plug for vehicle) is greatly adopted relative to the above mentioned electronic products. A power connecting electrode is extended from the center of a front end of a conventional electricity acquiring plug for vehicle and two lateral ends thereof respectively has a grounding connecting electrode with outward expanding resilient sheet, the rest part thereof is made of insulation materials; after the electricity acquiring plug for vehicle is inserted into an electricity acquiring socket, a guiding wire is used for outputting DC power so as to connect to the above mentioned portable electronic products.
For utilizing an electricity acquiring plug for vehicle available in a marketplace in a high current status, a means of increasing elastic forces of grounding and power connecting electrodes is often adopted, so each connecting electrode is ensured to have a sufficient connecting pressure. Said means would require a larger force for plugging or releasing the electricity acquiring plug for vehicle from an electricity acquiring socket; if the elastic force of the ground connecting electrode is overly high, the socket may be accidentally removed during an operation of releasing the electricity acquiring plug for vehicle.
Moreover, if the elastic force of the ground connecting electrode is not larger enough, connecting points of the power connecting electrode and the socket may be loosen because of vibration generated during driving the vehicle, so an inadequate connection may be generated and temperatures of the power connecting electrode and the connecting points are raised and the plastic housing may therefore melts, thus a fire may be occurred and a safety issue shall be concerned.